Anyone tried the Rail Ryder system?
+1 with Sinovac. They look slick, but they're $12k. The inventor will tell you that it's no big deal to haul a bike or sled or side by side etc, but after you see one in person, it just looks like there is too much expensive aluminum structure in the way to just simply walk or drive something into the trailer and tie it down. After a summer of tracking with my new inTech, I'm glad I saved $10k with a winch and some race ramps - it's 95% as safe and faster. Furthermore, if it were to somehow fail at the track (or car show) there's really no way to load your car.